Description
In the Linux kernel, the following vulnerability has been resolved:

wifi: ath6kl: clamp assoc request/response lengths before subtracting IE offsets

ath6kl_cfg80211_connect_event() subtracts fixed IE offsets from
assoc_req_len (-= 4) and assoc_resp_len (-= 6), both u8, with no lower
bound. The aggregate check recently added to ath6kl_wmi_connect_event_rx()
bounds the declared lengths from above (their sum must fit the received
event), but an assoc request/response shorter than its fixed offset still
underflows here: the u8 wraps to ~250, and cfg80211_connect_result() /
cfg80211_roamed() then treat that wrapped value as the IE length and copy
that many bytes out of the small assoc_info buffer to user space via
nl80211, disclosing adjacent slab memory.

Clamp both lengths to their offsets before subtracting.

Found by 0sec (https://0sec.ai) using automated source analysis; the
missing lower bound is evident from source. Compile-tested.
Published: 2026-09-11
Score: 8.1 High
EPSS: < 1% Very Low
KEV: No
Impact: Information Disclosure
Action: Immediate Patch
AI Analysis

Impact

In the Linux kernel, the ath6kl driver performs a subtraction of fixed IE offsets from the association request and response lengths, which are unsigned 8‑bit values. Because no lower bound is checked, an underflow can occur, wrapping the value to a large number. The resulting over‑read copies data from adjacent slab memory into a user‑space buffer via nl80211, exposing sensitive information without any privilege escalation.

Affected Systems

The vulnerability exists in ath6kl co‑processor driver changes. Any distribution running a kernel with the unpatched ath6kl code is susceptible; no specific kernel versions are listed in the advisory.

Risk and Exploitability

The CVSS score of 6.4 indicates a moderate risk profile. The EPSS score of < 1% indicates a very low likelihood of exploitation, and the vulnerability is not included in the CISA KEV catalog. An attacker would need to lure the device to an attacker‑controlled Wi‑Fi access point that sends malformed association frames, a scenario that is feasible over the air. Successful exploitation results in leaking adjacent memory contents to the device user, which could aid further attacks.

Generated by OpenCVE AI on September 13, 2026 at 04:09 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Apply the latest kernel update or backport the patch that clamps the association lengths before subtraction.
  • If an immediate kernel upgrade Wi‑Fi co‑processor or block untrusted wireless networks to reduce exposure.
  • Maintain regular kernel maintenance and monitor vendor advisories for future updates.

Generated by OpenCVE AI on September 13, 2026 at 04:09 UTC.

Tracking

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Advisories

No advisories yet.

History

Sun, 13 Sep 2026 06:45:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 6.4, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:H'}

cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H'}


Sat, 12 Sep 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-125
References
Metrics threat_severity

None

cvssV3_1

{'score': 6.4, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:H'}

threat_severity

Important


Fri, 11 Sep 2026 23:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: wifi: ath6kl: clamp assoc request/response lengths before subtracting IE offsets ath6kl_cfg80211_connect_event() subtracts fixed IE offsets from assoc_req_len (-= 4) and assoc_resp_len (-= 6), both u8, with no lower bound. The aggregate check recently added to ath6kl_wmi_connect_event_rx() bounds the declared lengths from above (their sum must fit the received event), but an assoc request/response shorter than its fixed offset still underflows here: the u8 wraps to ~250, and cfg80211_connect_result() / cfg80211_roamed() then treat that wrapped value as the IE length and copy that many bytes out of the small assoc_info buffer to user space via nl80211, disclosing adjacent slab memory. Clamp both lengths to their offsets before subtracting. Found by 0sec (https://0sec.ai) using automated source analysis; the missing lower bound is evident from source. Compile-tested.
Title wifi: ath6kl: clamp assoc request/response lengths before subtracting IE offsets
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-09-13T06:30:23.489Z

Reserved: 2026-09-11T19:38:34.719Z

Link: CVE-2026-89524

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-11T20:19:35.137

Modified: 2026-09-13T07:17:14.833

Link: CVE-2026-89524

cve-icon Redhat

Severity : Important

Publid Date: 2026-09-11T19:44:05Z

Links: CVE-2026-89524 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-09-13T04:15:13Z

Weaknesses